Meter.



No. 730,613. PATENTED-IUNE 9. 1903.

P. P. COX.

METER.

APPLICATION FILED FEB. 24, 1903.

H0 MODEL.

Witnesses; Inventor-Q j 4 r nk P Cox.

UNITED STATES iEatented June 9, 1903.

PATENT OFFICE.

FRANK P. COX, OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERAL ELEC- TRIOCOMPANY, A CORPORATION OF NEW YORK.

METER.

SPECIFICATION forming part of Letters Patent No. 730,613, dated June 9,1903.

Application filed February 24, 1903. Serial No, 144,666. (No model.)

To all whom, it may concern:

Be it known that I, FRANK P. COX, a citizen of the United States,residing at Lynn, in the county of Essex, State of Massachusetts,

have invented certain new and useful Improvements in Meters, of whichthe following is a specification.

In electric meters of the ordinary construction the armature-shaft isvertically disposed. to Owing to the accurate operation required ofthese meters it is desirable that the friction between the shaft and itsbearings be made as little as possible.

In order to avoid any frictional trouble, I have provided means forsustaining the weight of the shaft and apparatus carried by it in suchmanner that no mechanical friction' due to the weight of the shaft canexist. The specific means which I have devised for this purpose comprisea novel arrangement of two members formed of magnetic material, one ofthese members being carried by the shaft and the other supportedindependently of the shaft. One or both of these members produces amagnetic flux, being magnetized permanently or by current-carryingcoils. The members are so arranged that the magnetic flux produced issufficient to partially or wholly support the weight of the shaft andelements carried by it.

For a better understanding of my invention reference may be had to theaccompanying drawing, which is a vertical elevation, partly in section,showing one embodiment 5 of my invention. 7

Referring to the drawing, 1 represents a supporting-frame of a meter ofthe ordinary construction. A vertical shaft 2 carries an armature 3,which rotates within the field 0 produced by a pair of coils 4, carriedby the frame 1. At the lower end of this shaft is placed a disk 5, whichcooperates with magnets 6 in the ordinary manner to produce theretarding force acting upon the armatureshaft. A tubular post 7, locatedat the bottom of the frame 1, carries at its upper end an annularbearing member 8. The lower end of the shaft 2 passes through thisannular member and is positioned by it. The hearing member 8 may be madeout of any suitable material-as, for instance, that used to form theordinaryjewel bearings of a meter. An electromagnet 9 of the iron-cladtype is secured in place at the upper end of the frame 1 in any suitablemanner, as by means of screws 10. The electromagnet 9 consists of a bodyportion 11, which is substantially per-. pendicular to the shaft 2, andpolar portions 12 and 13, which extend from the lower side of theportion 11. The polar extension 13 comprises an elongated cylindricalportion 14 and another cylindrical portion 15, having a diametersomewhat larger than the portion 14; Preferably the portions 14 and 15are integral, while the portion 14 is separable from the portion 11,being secured thereto by a screw 13. In the construction which I haveillustrated a coil 16 surrounds the portion 14- of the polar extension13, being held in place by the enlarged portion 15. The polar extension12 may be in the form of a cylindrical body, with its axis coincidingwith the axis of the shaft 2. The cylindrical portion 12 is provided atits lower end with an offset portion 17. I The inner portion 17 forms acylindrical surface, which surrounds the portion 15 of a polar extension13, and the magnetic flux produced by the coil 16 passes between theportion 1 1 and the portion 17 in radial lines.

The shaft 2 carries at its upper end a plurality of arms 18, preferablyformed of nonmagnetic material, and the arms 18 carry an annular mass ofmagnetic material, such as soft iron, which is of the proper dimensionsto substantially fill the annular space be tween the portions 15 and 17of the electromagnet 9. Preferably the member 19 is so proportioned asto leave small air-gaps 20 between it and the portions 15 and 17.

As will be readily understood, the magnetic flux passing between theportions 15 and 17 of the electromagnet 9 will tend to draw the armature19 to the position in which the magnetic reluctance of the circuit Willbe reduced to a minimum. It the parts are properly proportioned, thejoint act-ion of the electromagnet 9 and the armature 19 willbe to holdthe shaft in the position shown in the drawings, in which case theweight of the shaft and ar- I00 mature is supported wholly independentof any mechanical bearings.

In order to guard against accidental displacement of the upper end ofthe shaft 2, a bearing-ring 21, which may be similar to the bearing-ringS, is supported in an axial recess 22, formed in the lower end of thepolar extension 13. The bearing-ring 21 may be secured in position bymeans of a perforated threaded plug 23, screwed into the lower end of apolar extension 13, as shown. While I have shown an electromagnet as theflux-producing member, it will of course be understood that a permanentmagnet having the same shape could be employed.

Instead of making the peripheries of the portions 15 and 17 cylindrical,as shown and described, other shapes might be employed.

The construction which I have illustrated is especially desirable whenan electromagnet is employed as the flux-producing element, owing to theadvantageous location of the coil 16. The coil 16 may form a part of theresistance ordinarily included in the potential-circuit of a meter or itmay be supplied with current in any other suitable way.

While I have illustrated and described the best form of my inventionwhich is known to me, it will be readily understood that changes in theform, arrangement, and proportions of the constructions in which I haveembodied my invention may be made without departing from the spirit ofmy invention.

What I claim as new, and desire to secure by Letters Patent of theUnited States, is

1. In combination, a magnet having two poles one of which surrounds theother, and a rotatable annular armature formed of magnetic materialplaced between said poles and held in place by magnetic attraction.

2. In a magnetic suspension device, means for producing a radialmagnetic field, a shaft to be supported, and an annular armature carriedby said shaft and located in said magnetic field, the weight of saidshaft being supported by the interaction between the field and thearmature.

3. In a magnetic suspension device, a supporting member, a member to besupported, a magnet having two poles, one of which surrounds the other,and an annular armature placed in and substantially filling the spacebetween said poles, the magnet being carried by one of said members andthe armature by the other and the weight of the member to be supportedbeing sustained by the magnetic attraction between the magnet and thearmature.

4. In an electric meter, a vertical metershaft, an annular armaturecarried by the shaft, a magnet having a polar extension substantially inline with the axis of the shaft, and another polar extension surroundingthe first mentioned polar extension, the polefaces being so located thatthe magnetic flux produced is substantially at right angles to the axisof the shaft and through the annu lar armature which is in the spacebetween the two pole-pieces.

5. In combination, a supporting member, an electromagnet carried by saidsupporting member and provided with a central detachable pole-piecehaving an enlargement at its free end, its pole-face being formed by theperiphery of the enlargement, another polar extension surrounding thefirst and separated therefrom by an annular space, a member to besupported, and an armature composed of magnetic material carriedthereby, the magnetic material being shaped to substantially fill thespace between the pole-pieces.

6. In combination, a supporting member,

a shaft member mounted to have longitudinal movement relative to thesupporting member, and means for preventing such longitudinal relativemovement of the shaft member comprising a magnet having a polarprojection substantially in line with the shaft member, means forcausing the magnetic flux produced in the air-space surrounding saidpolar projection to travel in a plane substantially perpendicular to theshaft member, and an annular armature surrounding said polar projectionand traversed. by said flux, the armature being carried by one of saidmembers and the magnet being carried by the other of said members.

7. In an electric meter, a supporting member, a rotary shaft memberhaving freedom of movement longitudinally of its axis with respect tothe stationarymember, and means for preventing such longitudinalmovement of the shaft member comprising a magnet having two poles one ofwhich surrounds the other and an armature placed between the poles, themagnet being carried by one of the members and the armature by the otherof the members.

8. In an electric meter, a supporting member, a rotatable shaft member,and means for reducing the mechanical friction between the supportingmember and the shaft member comprising a magnet containing a polarextension substantially in line with the axis of the shaft member andanother polar extension surrounding the first-mentioned polar extension,the pole-faces being so located that the magnetic flux produced issubstantially at right angles to the axis of the shaft, a cooperatingelement arranged in the space between the two pole-faces, the magnetbeing carried by one of said members and the cooperating element beingcarried by the other of said members and the weight of the shaft memberbeing supportedby the interaction between the magnet and the cooperatingelement.

In witness whereof I have hereunto set my hand this 19th day ofFebruary, 1903.

FRANK P. COX.

WVitnesses:

DUGALD MoK. McKILLoP, ALEX. F. MACDONALD.

